*{
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Poppins', sans-serif;
}
body{
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  background: #fff;
}
.nav{
  width:100vw;
  height: 70px;
  padding: 0 45px;
  border-radius: 10px 10px 0 0 ;
  background-color: #80D7BE;
  position: relative;
  display: flex;
  li{
    width: 70px;
    height: 70px;
    z-index: 1;
    // flex: 1;
    position: relative;
    list-style: none;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    i{
      display: block;
      height: 70px;
      line-height: 70px;
      font-size: 24px;
      text-align: center;
      position: relative;
      transition: all 0.5s;
      color: #fff;
    }
    span{
      position: absolute;
      font-size: 12px;
      letter-spacing: 2px;
      transition: all .5s;
      opacity: 0;
      transform: translateY(20px);
      color: #fff;
    }
  }
}
.nav li.active i{
  transform: translateY(-35px);
  color: #fff;
}
.nav li.active span{
  opacity: 1;
  transform: translateY(10px);
}
.indicator{
  position: absolute;
  top: -50%;
  width: 70px;
  height: 70px;
  background: #80D7BE;
  border-radius: 50%;
  transition: all .5s;
  border: 6px solid rgba(255, 255, 255) ;
}
.indicator::before{
  content: '';
  position: absolute;
  top: 50%;
  left: -22px;
  width: 20px;
  height: 20px;
  background-color: orange;
  border-top-right-radius: 20px;
  box-shadow: 1px -10px 0 0 #fff;
  opacity: 0;
}
.indicator::after{
  content: '';
  position: absolute;
  top: 50%;
  right: -22px;
  width: 20px;
  height: 20px;
  background-color: orange;
  border-top-left-radius: 20px;
  box-shadow: -1px -10px 0 0 #fff;
  opacity: 0;
}
.indicator::before{
  background-color: #222327;
}
.indicator::after{
  background-color: #222327;
}
li:nth-child(1).active~.indicator{
  transform: translateX(calc(70px * 0));
}
li:nth-child(2).active~.indicator{
  transform: translateX(calc(70px * 1));
}
li:nth-child(3).active~.indicator{
  transform: translateX(calc(70px * 2));
}
li:nth-child(4).active~.indicator{
  transform: translateX(calc(70px * 3));
}
